The tribological properties and synergistic lubrication mechanism of MoS2/ AlOOH nanosheets as lubricant additives

The MoS2/AlOOH 2 /AlOOH nanocomposites were prepared through a facile one-pot hydrothermal method and subsequently employed as lubricating oil additives to improve the tribological properties of PAO4 base oil. The structure, composition, morphology, tribological properties, and lubrication mechanism of the MoS2/AlOOH 2 /AlOOH nanocomposites have been investigated. The results demonstrated that the in-situ assembly of MoS2 2 on the surface of AlOOH change their microstructure, resulting in enhanced dispersion and a reduction in friction and wear. At 0.5 wt% concentrations of MoS2/AlOOH 2 /AlOOH nanocomposites, the average COF, WSD, and wear volume were decreased by 50.47 %, 42.34 %, and 86.57 % compared to base oil, respectively. Moreover, the tribological behaviors of the PAO4 containing MoS2/AlOOH 2 /AlOOH nanocomposites under various conditions were explored as well. Furthermore, based on the analysis of micromorphology and composition of wear surfaces, a synergistic lubrication mechanism for MoS2/AlOOH 2 /AlOOH nanocomposites has been proposed, which involves the formation of a tribochemical film composed of Fe2O3, 2 O 3 , Fe3O4, 3 O 4 , MoS2, 2 , and Al2O3 2 O 3 and demonstrates remarkable capabilities in reducing friction and wear. This research might provide new insight into enhancing the tribological properties of MoS2-based 2-based additives through the composite method and promote the application of MoS2/AlOOH 2 /AlOOH nano- composites as additives.